Surveillance will be visually performed or compliance verified by means of samples, measures, laboratory tests or document reviews. The goal of surveillance is to verify that granted UL Marks are being used correctly and that products still comply with the safety and/or operation requirements specified by the normative documents and scheme requirements under which such products have been evaluated. The legitimacy of a product certificate or dictum depends on surveillance results.

Product surveillance is performed by means of inspections that take place at least once a year and are either scheduled in advance or administered at random.

Surveillance visits are classified as follows:

  • Preliminary inspection visits – scheduled visits that represent a product certification requirement under Certification Schemes II, VI, VII, VIII, and for Scheme III if a product dictum does not exist and its confirmation is required.
  • Routine surveillance visits (inspections) – visits to verify whether products still comply with tests and specifications under which a certification was granted. Applies to all certification schemes. These inspections do not require any confirmation and will occur according to UL’s availability. It could take place three months after the corresponding notification is received. However, in some cases, these inspections may take place after the contact person is personally notified.
  • Extraordinary visits – visits that may or may not be scheduled in advance to verify either the implementation of corrective measures regarding non-compliances detected previously or perform sampling requested or when it is requested by the authorities due to claims. Such visits will only take place upon explicit request by the manufacturer or the certification area or by explicit request of competent departments and authorities and applies at all certification schemes.

Important considerations:

  • UL schedules surveillance visits within the certificate’s lifespan.
  • UL will send the surveillance visit notification. For the case of scheduled visits, if the requested confirmation is not received within the deadline, the surveillance visit date and place will be considered accepted.
  • Upon receiving a scheduled surveillance visit notification and identifying scheduling conflicts, legal representatives or contact people must request, within the deadline indicated in the visit notification, that the visit is rescheduled. Visits can be rescheduled only one time at most.
  • Please keep in mind that the customer, manufacturer, owner, subordinates, and those in charge of industrial or commercial sites are responsible for allowing access and making the necessary facilities available for UL personnel to perform a surveillance visits.
  • In any case, during the surveillance visit, UL’s representative shall select the product samples corresponding to the products surveyed. (See “Activities that will take place during a surveillance visit / Product sampling).
  • Selected samples must be sent either to a laboratory that was subcontracted or validated by UL de México S.A. de C.V., or a lab with which UL de Mexico, S.A. de C.V. has a Mutual Recognition Agreement (MRA) signed.
  • If non-compliances are detected, they must be addressed within the deadline stated by the corresponding notice. If necessary, an extraordinary surveillance visit(s) will take place to review the implementation and effectiveness of corrective actions that were performed.
  • Changes or modifications to products must be notified or reported in writing to UL. UL will analyze such changes or modifications and may request additional product tests to evaluate whether the changes comply with safety or functionality requirements demanded by the corresponding standard.
  • Regarding certified product lots (Scheme VII and VIII) and Scheme V certifications, surveillance inspections will not be performed by UL de México. Product follow-up or surveillance process for these schemes is responsibility of the Dirección General de Normas (General Directorate of Standards) and PROFECO-Procuraduría Federal del Consumidor (Consumer Affairs Bureau) and will be performed at the respective point of sale to verify that products being sold comply with the category under which they were certified.

Activities that will take place during a surveillance visit (inspection) include:

  • Description of the surveillance visit’s scope and – identification of participants in the surveillance visit, as applicable.
  • Document review only for Schemes II, III and VI.
  • Quality system and production line audit for Scheme II or III, if national or foreign manufacturer product dictum does not exist or reconstruction line audit, for Scheme VI.
  • Product sampling – performed strictly as necessary for testing purposes according to the applicable standard. Samples are selected in pairs (except for Schemes VI, VII, and VIII) since one of them will be considered a control sample. The customer shall decide if a control sample will be selected, in which case it has to be indicated at the moment in which the UL’s representative is performing the sampling. Control samples will be used in case of concerns or when the test report results or technical analysis results are negative. Control samples are kept for the customer and they will be made available again once UL de México issues a favorable response. If you decide not to provide a control sample and one is later required, you must request that UL de México make an extraordinary surveillance visit for product sampling. UL will perform the visit with the respective charge.

    The first verification shall be conducted on the sampled product and, if positive results are obtained from the laboratory, UL de México generates the “Notice of Compliance” for such certificate. On the opposite case, UL de Mexico will notify, via written communication, the suspension of the certificate.

    In the case where the result of the first verification is negative and the customer has decided to keep a control sample, it has to be evaluated and notifying this to UL. It shall take place into the following five working days after the corresponding notification is received.

  • If the certificate issued contents more than one model, the model to be sampled, will be preferably different from the model originally evaluated or not sampled before.
  • Product review for Marks and Mark usage.
  • Summary of activities -UL’s representative fills out the Inspection Report. As applicable, observations will be made and detected deviations will be explained if necessary. UL’s representative will leave a copy (either hard copy or in electronic format) of the applicable Inspection Report form for reference.

Reasons for suspension of the certification

UL will suspend a NOM certificate when:

  • If non-compliances are detected and attributed to the customer regarding any obligations stated in the service agreement and/or Scheme requirements and/or normative document under which the product was evaluated.
  • UL detects changes made on certified products and such changes were not notified to UL.
  • Surveillance inspection or sampling product cannot be performed due to an imputable cause to the customer.
  • Confirming or determining during an evaluation performed due to third party claims or reports, that the certified product is not in compliance with the applicable requirements with which it was evaluated.
    During this term, suspended certificates or certification Marks shall not be used and UL will apply the necessary measures for the customer to suspend their use. Once pertinent corrections or clarifications are made, UL will conduct an extraordinary inspection to verify whether they were effectively implemented or request complementary tests, as applicable.
    During this term, suspended certificates or certification Marks shall not be used and UL will apply the necessary measures for the customer to suspend their use. Once pertinent corrections or clarifications are made, UL will conduct an extraordinary inspection to verify whether they were effectively implemented or request complementary tests, as applicable.

Reasons for cancellation or certification withdrawal

UL will cancel or remove a NOM certificate and/or dictum when:

  • Customer does not implement, in the period time established by UL, corrections required for fixing the non-conformances detected,
  • Features product established by the certificate and/or dictum are not met,
  • UL proves that granted certificates or dicta have been altered or forged,
  • UL’s representative designated for a surveillance visit, cannot take place it because the company or address does not exist,
  • UL receives a customer’s explicit request, by means of a written notice issued in advance,
  • An ownership extension is granted and some importers, distributors or sellers misuse a granted certificate or dictum, or their commercial relationship to the certificate’s owner has finished,
  • Certification Marks are misused,
  • If the result of the sampled product evaluated is negative and the customer does not request, in the period of time established, the extraordinary visit required,
  • The result of the control sample evaluated is negative,
  • Sampled Product Test Report (surveillance Test Report) was not received within the period of time established.

If non-compliances are not corrected according to the aforementioned terms, UL will cancel the respective certificate or dictum and issue a written notification terminating the service, without detriment to applicable sanctions according to the Ley Federal Sobre Metrología y Normalización (Federal Law on Metrology and Standardization), the Federal Consumer Protection Law, and other applicable laws.

In any of the cases mentioned above, you must not use cancelled certificates or dictums, as well as, the UL-MX NOM conformity marks neither in the product nor publicity or advertising materials. On the opposite way, UL will proceed to apply all necessary measures for avoiding the customer to continue the use of their conformity marks.

Periods of time established

UL has established different periods of time for activities in which an answer is required from the customer. The period of time begins from the next day in which either the customer receives a UL notification or the sampling product was done, as applicable.

Activities Type of Visit Period
VP VR VE # days Type
Confirm a non -scheduled visit X 5 Working
Confirm a scheduled visit X X 3 Working
Submit sampled product’s test report X X 45 Calendar
Submit control sample’s test report X 30 Calendar
Control samples are kept for customer* *
Sending control sample to the lab, as applicable 5 Working
Requesting surveillance visit X 5 Working
Notify by written the corrective action to be taken whether non-conformances were detected X X X 5 Working
Close of non-conformances detected **


* Control sample will be made available again once UL de México issues a favorable response.

** Maximum 30 (thirty) calendar days or the period that UL de Mexico establishes for that.